13 research outputs found
Brazilian disk tests: Circular holes and size effects
Abstract Size effects related to circular notched samples imply that the strength of the structure decreases as the hole radius increases. In this framework, Brazilian disk tests are carried out on brittle samples containing a circular hole. By considering two different polymers, namely Polymethyl-methacrylate (PMMA) and General-purpose Polystyrene (GPPS), respectively, five different notch radii were machined and tested for each material, keeping low the hole to disk diameter ratio in order to reproduce an infinite geometry. Under this assumption, analytical relationship for the stress field and the stress intensity factor can be implemented without loss of accuracy. The coupled finite fracture mechanics (FFM) is then applied to catch the recorded failure stresses, allowing a complete description of the experimental size effects. On the contrary, the smallest radius leads to a locally negative geometry, opening the discussion on the stability of crack propagation in circularly notched plates under generic biaxial loadings
Search for natural and split supersymmetry in proton-proton collisions at TeV in final states with jets and missing transverse momentum
A search for supersymmetry (SUSY) is performed in final states comprising one or more jets and missing transverse momentum using data from proton-proton collisions at a centre-of-mass energy of 13 TeV. The data were recorded with the CMS detector at the CERN LHC in 2016 and correspond to an integrated luminosity of 35.9 fb−1. The number of signal events is found to agree with the expected background yields from standard model processes. The results are interpreted in the context of simplified models of SUSY that assume the production of gluino or squark pairs and their prompt decay to quarks and the lightest neutralino. The masses of bottom, top, and mass-degenerate light-flavour squarks are probed up to 1050, 1000, and 1325 GeV, respectively. The gluino mass is probed up to 1900, 1650, and 1650 GeV when the gluino decays via virtual states of the aforementioned squarks. The strongest mass bounds on the neutralinos from gluino and squark decays are 1150 and 575 GeV, respectively. The search also provides sensitivity to simplified models inspired by split SUSY that involve the production and decay of long-lived gluinos. Values of the proper decay length cτ0 from 10−3 to 105 mm are considered, as well as a metastable gluino scenario. Gluino masses up to 1750 and 900 GeV are probed for cτ0 = 1 mm and for the metastable state, respectively. The sensitivity is moderately dependent on model assumptions for cτ0 ≳ 1 m. The search provides coverage of the cτ0 parameter space for models involving long-lived gluinos that is complementary to existing techniques at the LHC
Colour image gradient regression reintegration
Suppose we process an image and alter the image gradients in each colour channel R,G,B. Typically the two new x and y component fields p,q will be only an approximation of a gradient and hence will be nonintegrable. Thus one is faced with the problem of reintegrating the resulting pair back to image, rather than derivative of image, values. This can be done in a variety of ways, usually involving some form of Poisson solver. Here, in the case of image sequences or video, we introduce a new method of reintegration, based on regression from gradients of log-images. The strength of this idea is that not only are Poisson reintegration artifacts eliminated, but also we can carry out the regression applied to only thumbnail images. The novel approach here is to regress derivatives (using only thumbnails) and then replace reintegration itself by the much simpler use of the resulting regression coefficients on non-derivative, full-size images. We investigate the utility of the method by applying it to the intrinsic-image problem as a first test, and then also to the night-to-day problem as a second test. We find that the new algorithm performs well, and is fast. Moreover eliminating Poisson artifacts results in clearer, more sharp output images that can show far less ghosting
Red yeast rice as an adjunct to sertraline for treatment of depression in patients with percutaneous coronary intervention: Placebo-controlled trial
Objectives: Red yeast rice (RYR) has demonstrated neuroprotective effects in animal studies. The aim of this study was to access the efficacy of RYR for treatment of depression in patients with recent history of percutaneous coronary intervention. Design: This was a 6-week double-blind placebo-controlled randomized clinical trial. Setting: Participants included outpatient men and women aged 18 to 60 years old with history of coronary angioplasty, diagnosis of major depressive disorder based on the Diagnostic and Statistical Manual of Mental Disorders (DSM-V), and Hamilton Depression Rating Scale (HDRS) score of �20. Candidates were excluded in case of any other DSM-V disorders, use of lipid lowering agents in the last two weeks, elevated serum aminotransferases or serum LDL � 80 mg/dL. Interventions: Patients received sertraline (200 mg/day) plus either red yeast rice commercially available capsules (2400 mg/day) containing 10.05 mg/day lovastatin or placebo. Main outcome measures: The primary outcome was the difference in mean change of the HDRS score from baseline to endpoint between the two treatment arms. Results: The primary outcome approached significance (Mean difference in score change(CI95) = �1.24 (�2.51 to 0.03), p =.056) and was accompanied by a significant time � treatment interaction effect Two-way ANOVA: F (df, mean square) = 4.42 (2, 13.687), p =.015. There was no significant difference between the two treatment arms in terms of lipid profile, liver function tests, or incidence of adverse events. Conclusions: This is the first report on the benefits of RYR in treatment of depression. Future studies are warranted to confirm our findings and scrutinize the mechanisms of action. © 2018 Elsevier Lt
Red yeast rice as an adjunct to sertraline for treatment of depression in patients with percutaneous coronary intervention: Placebo-controlled trial
Objectives: Red yeast rice (RYR) has demonstrated neuroprotective effects in animal studies. The aim of this study was to access the efficacy of RYR for treatment of depression in patients with recent history of percutaneous coronary intervention. Design: This was a 6-week double-blind placebo-controlled randomized clinical trial. Setting: Participants included outpatient men and women aged 18 to 60 years old with history of coronary angioplasty, diagnosis of major depressive disorder based on the Diagnostic and Statistical Manual of Mental Disorders (DSM-V), and Hamilton Depression Rating Scale (HDRS) score of �20. Candidates were excluded in case of any other DSM-V disorders, use of lipid lowering agents in the last two weeks, elevated serum aminotransferases or serum LDL � 80 mg/dL. Interventions: Patients received sertraline (200 mg/day) plus either red yeast rice commercially available capsules (2400 mg/day) containing 10.05 mg/day lovastatin or placebo. Main outcome measures: The primary outcome was the difference in mean change of the HDRS score from baseline to endpoint between the two treatment arms. Results: The primary outcome approached significance (Mean difference in score change(CI95) = �1.24 (�2.51 to 0.03), p = .056) and was accompanied by a significant time � treatment interaction effect Two-way ANOVA: F (df, mean square) = 4.42 (2, 13.687), p = .015. There was no significant difference between the two treatment arms in terms of lipid profile, liver function tests, or incidence of adverse events. Conclusions: This is the first report on the benefits of RYR in treatment of depression. Future studies are warranted to confirm our findings and scrutinize the mechanisms of action. © 2018 Elsevier Lt
Red yeast rice as an adjunct to sertraline for treatment of depression in patients with percutaneous coronary intervention: Placebo-controlled trial
Objectives: Red yeast rice (RYR) has demonstrated neuroprotective effects in animal studies. The aim of this study was to access the efficacy of RYR for treatment of depression in patients with recent history of percutaneous coronary intervention. Design: This was a 6-week double-blind placebo-controlled randomized clinical trial. Setting: Participants included outpatient men and women aged 18 to 60 years old with history of coronary angioplasty, diagnosis of major depressive disorder based on the Diagnostic and Statistical Manual of Mental Disorders (DSM-V), and Hamilton Depression Rating Scale (HDRS) score of �20. Candidates were excluded in case of any other DSM-V disorders, use of lipid lowering agents in the last two weeks, elevated serum aminotransferases or serum LDL � 80 mg/dL. Interventions: Patients received sertraline (200 mg/day) plus either red yeast rice commercially available capsules (2400 mg/day) containing 10.05 mg/day lovastatin or placebo. Main outcome measures: The primary outcome was the difference in mean change of the HDRS score from baseline to endpoint between the two treatment arms. Results: The primary outcome approached significance (Mean difference in score change(CI95) = �1.24 (�2.51 to 0.03), p = .056) and was accompanied by a significant time � treatment interaction effect Two-way ANOVA: F (df, mean square) = 4.42 (2, 13.687), p = .015. There was no significant difference between the two treatment arms in terms of lipid profile, liver function tests, or incidence of adverse events. Conclusions: This is the first report on the benefits of RYR in treatment of depression. Future studies are warranted to confirm our findings and scrutinize the mechanisms of action. © 2018 Elsevier Lt
A successful implementation of an idea to a nationally approved plan: Analyzing Iran's national health roadmap using the kingdon model of policymaking
Introduction: Hospital beds, human resources, and medical equipment are the costliest elements in the health system and play an essential role at the time of treatment. In this paper, different phases of the NEDA 2026 project and its methodological approach were presented and its formulation process was analysed using the Kingdon model of policymaking. Methods: Iran Health Roadmap (NEDA 2026) project started in March 2016 and ended in March 2017. The main components of this project were hospital beds, clinical human resources, specialist personnel, capital medical equipment, laboratory facilities, emergency services, and service delivery model. Kingdon model of policymaking was used to evaluate NEDA 2026 development and implementation. In this study, all activities to accomplish each step in the Kingdon model was described. Results: The followings were done to accomplish the goals of each step: collecting experts' viewpoint (problem identification and definition), systematic review of the literature, analysis of previous experiences, stakeholder analysis, economic analysis, and feasibility study (solution appropriateness analysis), three-round Delphi survey (policy survey and scrutinization), and intersectoral and interasectoral agreement (policy legislation). Conclusion: In the provision of an efficient health service, various components affect each other and the desired outcome, so they need to be considered as parts of an integrated system in developing a roadmap for the health system. Thus, this study demonstrated the cooperation process at different levels of Iran's health system to formulate a roadmap to provide the necessary resources for the health sector for the next 10 years and to ensure its feasibility using the Kingdon policy framework. © Iran University of Medical Sciences